Storyline triggers based on attempt count not working as expected

Based on the behavior you've observed, I'd guess that your AttemptCount variable isn't getting above 2. When working with variables, I highly recommend showing the variable value in a temporary text box on the slide. That helps with troubleshooting, because you can see whether the variable changes as expected. 

That said, I think you're making more work for yourself than is needed. Since it's a graded question slide set to 3 attempts, you could do this to get the behavior you want: 

• Use a T/F variable to track whether an attempt has been made. The default = False. The Try Again button adjusts it to True. 
• On the Try Again layer, use that variable to determine what message to show the user. For example, if it's False, show the Normal state of the text box. Otherwise, show a custom state with another message. 
• Keep both the Correct and Incorrect layers. Adjust the layout to blank, and delete all the content. Add 2 triggers to those layers. The first trigger hides the layer when the layer's timeline begins. The second trigger jumps to the next slide. 

This is demonstrated in the attached file.